The automotive original equipment market for cigar lighters accounts for millions of units per year. A constant search goes on for materials and methods which will reduce the cost by as much as a fraction of a penny.
The plug portion of an automotive cigar lighter conventionally consists of a pair of telescoping hollow tubes with a coil bias spring retained in the annular chamber between them. An inner member having a burner and burner cup at one end, and means for attaching a handle at the other end, occupies the center of the inner member. The burner cup prevents withdrawal of the inner member from the hollow tubes in one direction. Normally a flange at the second end of the inner member prevents withdrawal of the inner member in the second direction from the hollow tubes. U.S. Pat. No. 2,667,562 teaches a cigar lighter with an inner cup having an outward opening cone shape with a seating flange at its end. A disc containing a threaded hole is staked into the end of the inner cup by deforming the cup material into notches in the disc at three points about its perimeter. This assembly method is relatively time consuming because the disc and staking tools must be angularly oriented before affixing the disc. Staked assembly is also shown in U.S. Pat. Nos. 3,040,160 and 2,531,901. U.S. Pat. No. 2,895,036 teaches the use of a disc with a threaded hole placed inside a cup adjacent to a flange staked in place by deforming the metal of the cup inboard of the disc. The knob has a flange which retains the assembly together when a threaded knob shaft is threaded into the threaded hole in the disc.